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11 – 20 of over 19000The aim of the present work was to study the synergistic effect of HEDP and zinc on inhibition of the corrosion of carbon steel in neutral oxygen‐containing chloride solutions…
Abstract
Purpose
The aim of the present work was to study the synergistic effect of HEDP and zinc on inhibition of the corrosion of carbon steel in neutral oxygen‐containing chloride solutions, and to investigate the effect of zinc‐HEDP molar ratio on the effectiveness of the zinc‐HEDP inhibitive mixtures.
Design/methodology/approach
The inhibition of the corrosion of carbon steel by zinc‐HEDP mixtures in neutral oxygen‐containing solutions was investigated in the presence of 0.003 M (106 ppm) chloride.
Findings
It was shown that the inhibition by these mixtures depended not only on the zinc/HEDP molar ratio but also on the concentration of both zinc and HEDP. HEDP concentration appeared to be crucial where good inhibition was not achieved at low concentrations and aggressive nature is observed at high HEDP levels. The effectiveness of the zinc‐HEDP mixtures enhanced inhibition by increasing the zinc content of the mixture, but the mechanism was only effective to a certain level, above which the inhibition effect declined. The predominant corrosion control mechanism of the zinc‐HEDP mixture was on the anodic (metal dissolution) reaction, but it also affected the rate and mechanism of the oxygen reduction reaction.
Originality/value
Demonstrates how the effectiveness of the zinc‐HEDP mixtures can enhance inhibition by increasing the zinc content of the mixture.
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Bahaa Saleh, A. Abouel-Kasem and Shemy Ahmed
This paper aimed to analyze removed particles from stationary specimen-aluminum (Al-99.92) produced by vibratory cavitation erosion tests in distilled water and glycerol-water…
Abstract
Purpose
This paper aimed to analyze removed particles from stationary specimen-aluminum (Al-99.92) produced by vibratory cavitation erosion tests in distilled water and glycerol-water mixtures.
Design/methodology/approach
The particle morphology which include particle surface topography, size distribution, particle size parameters and particle shape parameters were examined for distilled water and glycerol-water mixtures having different viscosities.
Findings
The results showed that the variation of size parameters with viscosity was very similar to the variation of weight loss with viscosity. Both the size parameters and weight losses show a monotonic decrease in going from distilled water to glycerol-water mixtures having viscosity about 10.1 cSt, beyond which the change is very small. On the other hand, the shape parameters were much less sensitive to distinguish between the particles produced in water and glycerol-water mixtures. The mechanism of cavitation erosion is investigated in detail through observations of the removed particles. The particle surfaces topography demonstrated that the mechanism in water and glycerol-water mixtures was fatigue failure.
Originality/value
Cavitation often occurs in almost all machines that handle liquids, especially at high speeds, leading to irreparable damage of the components of these machines. Elucidation of such complex phenomenon demands full characterization of the erosion mechanism and controlling parameters inherent to it, so that cavitation erosion can be prevented or at least be reduced through adequate information and collection of relevant data under different operating conditions. Very few studies have been made to approach the viscosity effect upon cavitation erosion from the particle analysis standpoint. The aim of the present work is to identify the effect of liquid viscosity on the size, shape characteristics of the erosion particles and their morphological features. The prevailed mechanisms of wear and particle generation have been proposed based on the acquired information from particle analysis.
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The aim of this study was to produce an enriched honey powder with active compounds coming from bee pollen and investigate the effects of bee pollen addition as a carrier material…
Abstract
Purpose
The aim of this study was to produce an enriched honey powder with active compounds coming from bee pollen and investigate the effects of bee pollen addition as a carrier material on honey powder.
Design/methodology/approach
The effects of bee pollen addition as carrier material in corporation with gum arabic at different ratios (25, 50 and 75% of total carrier material amount) on vacuum-dried honey-bee pollen powder were investigated.
Findings
The bee pollen concentration raise in the mixture increased the particle size, total phenolic, flavonoid and sugar contents and antioxidant activity, whereas decreased the Hauser ratio and Carr index values, hygroscopicity and solubility of enriched honey powder samples. The honey powder samples had passable and poor flow properties and very hygroscopic (>20%) structure because of the high sugar content. The phenolic and flavonoid contents of honey powder samples with bee pollen changed between 1531.59 and 3796.00 mg GAE/kg and 424.05–1203.10 mg QE/kg, respectively, and these values were much higher than the control sample. On the basis of linear correlation analysis, there was a very high positive correlation between total phenolic, flavonoid and antioxidant activity, while there was a very high negative correlation between these parameters and solubility.
Originality/value
The study evaluated that enriching of honey powders with pollen, which is a product of both plant and bee origin, rather than enriching with different plant and animal sources has an innovative approach. Additionally, the usage of bee pollen as a carrier agent in food drying has not been previously reported in any study.
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The purpose of this paper is to examine the problem of tracing criminal proceeds through fungible mixtures, in the context of money laundering prosecutions and with a specific…
Abstract
Purpose
The purpose of this paper is to examine the problem of tracing criminal proceeds through fungible mixtures, in the context of money laundering prosecutions and with a specific focus on whether clean withdrawals can be made from tainted mixtures.
Design/methodology/approach
The question of withdrawing clean funds from a tainted mixture is framed as a problem of proof rather than a problem of impossibility. The tracing rules are then engaged to overcome evidential difficulties, but the rules are shown to operate very differently in civil proceedings and criminal proceedings. The proper application of the tracing rules in criminal proceedings is then illustrated using the facts of William v R [2013] EWCA Crim 1262.
Findings
Because evidential uncertainties must be resolved in favour of the accused person in criminal proceedings, the tracing rules – properly applied – limit the range of situations in which the Prosecution can successfully trace criminal proceeds through fungible mixtures.
Originality/value
This paper may be useful to law enforcement, those involved in prosecuting or defending money laundering cases and regulated persons assessing their money laundering risks and disclosure obligations.
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Faid Hayette, Abadou Yacine and Ghrieb Abderrahmane
The purpose of this paper is to characterize the properties lightweight green air lime and marble waste mixtures, relating microstructural and chemical properties with physical…
Abstract
Purpose
The purpose of this paper is to characterize the properties lightweight green air lime and marble waste mixtures, relating microstructural and chemical properties with physical development of the material, an effort has been made to simulate the structure of the different mortar reinforced by two main layers plants.
Design/methodology/approach
This paper presents an experimental design of response surface methodology, a model which predicts the mechanical strength and evaluate the effectiveness of bio-waste as a corrosion inhibitor to resist the steel corrosion in air lime mortars as a function of the proportion of the constituents of a new air lime mortar based on a combination of different percentages of marble waste (MRW), air lime and deferent type, layers of natural fiber reinforcement. Luffa sponge gourd and oakum hemp fiber residues capabilities in civil engineering are evaluated by combining numerical and experimental approaches for repair mortar based on air lime and marble waste. Several electrochemical techniques, mechanical strength tests and visual inspection of steel surface were performed.
Findings
The results revealed good mechanical strength and corrosion protection properties of air lime mortar containing the fiber naturel. These green wastes are considered economically feasible, as well having possessing good performance efficiency in protecting rebar reinforcement. These results were confirmed via polarization curves and electrochemical impedance spectroscopy measurements.
Originality/value
The prepared green air lime mortar provided good corrosion protection to the rebar. The significance of this study is to encourage the usage of solid white marble waste to prepare biomass-based repair mortar with good mechanical and anti-corrosion properties on the long term is still a big challenge.
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The purpose of this paper is to demonstrate applicability of the pervaporation technique for separation ethanol/water mixtures.
Abstract
Purpose
The purpose of this paper is to demonstrate applicability of the pervaporation technique for separation ethanol/water mixtures.
Design/methodology/approach
For the purposes of membrane material development for pervaporation zeolite filled and unfilled cellulose acetate membranes were prepared. Zeolite types were 4A, 13X. The effect of incorporation of nano‐sized zeolites prepared in a colloidal form in membranes was also investigated. Equilibrium sorption experiments were carried out. Degrees of swelling were calculated at different liquid feed mixture compositions for separating an azeotrope forming mixture, ethanol/water by pervaporation.
Findings
Zeolite 13X filled CA membrane may have the better pervaporation performance than zeolite 4A filled CA membrane. From the sorption tests it is concluded that ethanol/water azeotropy can be achieved by pervaporation.
Practical implications
Application of CA membranes in industrial scale pervaporation units may be feasible for separation of ethanol/water mixtures. Specially ethanol/water azeotropy will be achieved by pervaporation. Using distillation and pervaporation hybrid systems, bioethanol can be produced economically.
Orginality/value
The paper illustrates the success of pervaporation techniques in separating ethanol/water mixtures.
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F.T. Seyidov, Y. Mansoori and J. Taghi Nezhad
This paper seeks to address the preparation of new compositions of hydrophobicizing liquids as release agent for press moulds in the production of plastic articles of all kinds of…
Abstract
Purpose
This paper seeks to address the preparation of new compositions of hydrophobicizing liquids as release agent for press moulds in the production of plastic articles of all kinds of polymers.
Design/methodology/approach
Mixtures of thermo‐stable polyethers (copolymer of ethylene oxide and propylene oxide) and polyols esters/mixed esters in the presence of phenothiazine as antioxidant were prepared and tested.
Findings
All compositions were tested and compared with silicone oil polymethylsiloxane‐100 (PMS‐100). The lubricant was manually applied on a hot surface (160‐190°C) of tray of press mould, without any change in the operating cycle. The finished products were easily removed from press mould, and showed higher durability. The release agent was also checked for production of polyethylene lids by automatic moulding at 170‐200°C, and 17 lids have been obtained on one application. This is quite a good result compared with silicone oil PMS‐100, which produced only four to five lids.
Research limitations/implications
Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern spectroscopy techniques.
Practical implications
In order to obtain compositions of optimum properties a lot of mixtures were prepared and tested. Only compositions which showed suitable properties were reported.
Originality/value
This paper provides detailed information on the experimental preparation of 37 compositions for hydrophobicizing mould release agents. Testing of different obtained hydrophobicizing liquids showed positive results, in production of plastic household articles, over silicone oil PMS‐100. The finished products were easily removed from press mould and prepared hydrophobicizing liquids showed higher durability than silicone oil PMS‐100. The obtained compositions are also favored from the point of view of commercial availability and ecology and can be considered as replacements for PMS‐100 release agent.
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Sajad Pirsa and Fardin Mohammad Nejad
The purpose of this paper is to construct an array of sensors using polypyrrole–zinc oxide (PPy–ZnO) and PPy–vanadium (V; chemical formula: V2O5) fibers. To test responses of…
Abstract
Purpose
The purpose of this paper is to construct an array of sensors using polypyrrole–zinc oxide (PPy–ZnO) and PPy–vanadium (V; chemical formula: V2O5) fibers. To test responses of sensors, a central composite design (CCD) has been used. The results of the CCD technique revealed that the developed sensors are orthogonally sensitive to diacetyl, lactic acid and acetic acid. In total, 20 different mixtures of diacetyl, lactic acid and acetic acid were prepared, and the responses of the array sensors were recorded for each mixture.
Design/methodology/approach
A response surface regression analysis has been used for correlating the responses of the sensors to diacetyl, lactic acid and acetic acid concentrations during the gas phase in food samples. The developed multivariate model was used for simultaneous determination of diacetyl, lactic acid and acetic acid concentrations. Some food samples with unknown concentrations of diacetyl, lactic acid and acetic acid were provided, and the responses of array sensors to each were recorded.
Findings
The responses of each sensor were considered as target response in a response optimizer, and by an overall composite desirability, the concentration of each analyte was predicted. The present work suggests the applicability of the response surface regression analysis as a modeling technique for correlating the responses of sensor arrays to concentration profiles of diacetyl, lactic acid and acetic acid in food samples.
Originality/value
The PPy–ZnO and PPy–V2O5 nanocomposite fibers were synthesized by chemical polymerization. The provided conducting fibers, PPy–ZnO and PPy–V2O5, were used in an array gas sensor system for the analysis of volatile compounds (diacetyl, lactic acid and acetic acid) added to yogurt and milk samples.
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Sadia Siddiqa, M. Anwar Hossain and Suvash C Saha
The purpose of this paper is to conduct a detailed investigation of the two-dimensional natural convection flow of a dusty fluid. Therefore, the incompressible boundary layer flow…
Abstract
Purpose
The purpose of this paper is to conduct a detailed investigation of the two-dimensional natural convection flow of a dusty fluid. Therefore, the incompressible boundary layer flow of a two-phase particulate suspension is investigated numerically over a semi-infinite vertical flat plate. Comprehensive flow formations of the gas and particle phases are given in the boundary layer region. Primitive variable formulation is employed to convert the nondimensional governing equations into the non-conserved form. Three important two-phase mechanisms are discussed, namely, water-metal mixture, oil-metal mixture and air-metal mixture.
Design/methodology/approach
The full coupled nonlinear system of equations is solved using implicit two point finite difference method along the whole length of the plate.
Findings
The authors have presented numerical solution of the dusty boundary layer problem. Solutions obtained are depicted through the characteristic quantities, such as, wall shear stress coefficient, wall heat transfer coefficient, velocity distribution and temperature distribution for both phases. Results are interpreted for wide range of Prandtl number Pr (0.005-1,000.0). It is observed that thin boundary layer structures can be formed when mass concentration parameter or Prandtl number (e.g. oil-metal particle mixture) are high.
Originality/value
The results of the study may be of some interest to the researchers of the field of chemical engineers.
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Sirine Ben Slima, Naourez Ktari, Mehdi Triki, Imen Trabelsi, Hafedh Moussa, Skandar Makni, Asehraou Abdeslam, Ana Maria Herrero, Francisco Jiménez-Colmenero, Claudia Ruiz-Capillas and Riadh Ben Salah
The purpose of this paper is to investigate the influence of different dietary fibers on color, nutritional, physico-chemical, sensory and textural properties of fresh sausage.
Abstract
Purpose
The purpose of this paper is to investigate the influence of different dietary fibers on color, nutritional, physico-chemical, sensory and textural properties of fresh sausage.
Design/methodology/approach
This study was undertaken to determine the effects of partial beef meat substitution (15, 10.5 and 6 percent) at different combinations: barley beta-glucan concentrate (BBC at 1 percent) alone, carrot fiber (ID809 at 1 percent) alone and a mixture of both fibers (BBC and ID809 at 0.5 percent of each), on the quality of fresh sausage.
Findings
Results revealed that the supplementation of dietary fibers generally decreased protein contents and increased moisture. Color parameters were significantly affected by the addition of dietary fibers. Meat substitution with dietary fibers tended toward red coloration, which enhanced sensory properties of fresh sausages, especially general acceptability. Fresh sausages formulated with a mixture of dietary fibers recorded good firmness. Indeed, it increased extrusion force values and provided a greater hardness at sensory level. This manuscript reports that beef sausage formulated with a mixture of BBC and ID809 and reduced beef meat rate improved acceptability to consumer.
Originality/value
The paper approaches a new subject that may be relevant to functional food. There are few research works to evaluate consumer preferences of new product developments and to achieve healthier and more economic fresh sausages formulated with a mixture of two fibers after reducing beef meat content.
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